Infinite Families of Gauge-Equivalent RR-Matrices and Gradations of Quantized Affine Algebras

Associated with the fundamental representation of a quantum algebra such as $U_q(A_1)$ or $U_q(A_2)$, there exist infinitely many gauge-equivalent $R$-matrices with different spectral-parameter dependences. It is shown how these can be obtained by examining the infinitely many possible gradations of the corresponding quantum affine algebras, such as $U_q(A_1^{(1)})$ and $U_q(A_2^{(1)})$, and explicit formulae are obtained for those two cases. Spectral-dependent similarity (gauge) transformations relate the $R$-matrices in different gradations. Nevertheless, the choice of gradation can be physically significant, as is illustrated in the case of quantum affine Toda field theories.Comment: 14 pages, Latex, UQMATH-93-10 (final version for publication

COVID-19 vaccine hesitancy among non-refugees and refugees in Kenya

Factors associated with COVID-19 vaccine hesitancy (which we define as refusal to be vaccinated when asked, resulting in delayed or non- vaccination) are poorly studied in sub-Saharan Africa and among refugees, particularly in Kenya. Using survey data from wave five (March to June 2021) of the Kenya Rapid Response Phone Survey (RRPS), a household survey representative of the population of Kenya, we estimated the self-reported rates and factors associated with vaccine hesitancy among non-refugees and refugees in Kenya. Non-refugee households were recruited through sampling of the 2015/16 Kenya Household Budget Survey and random digit dialing. Refugee households were recruited through random sampling of registered refugees. Binary response questions on misinformation and information were transformed into a scale. We performed a weighted (to be representative of the overall population of Kenya) multivariable logistic regression including interactions for refugee status, with the main outcome being if the respondent self-reported that they would not take the COVID-19 vaccine if available at no cost. We calculated the marginal effects of the various factors in the model. The weighted univariate analysis estimated that 18.0% of non-refugees and 7.0% of refugees surveyed in Kenya would not take the COVID-19 vaccine if offered at no cost. Adjusted, refugee status was associated with a -13.1[95%CI:-17.5,-8.7] percentage point difference (ppd) in vaccine hesitancy. For the both refugees and non-refugees, having education beyond the primary level, having symptoms of COVID-19, avoiding handshakes, and washing hands more often were also associated with a reduction in vaccine hesitancy. Also for both, having used the internet in the past three months was associated with a 8.1[1.4,14.7] ppd increase in vaccine hesitancy; and disagreeing that the government could be trusted in responding to COVID-19 was associated with a 25.9[14.2,37.5]ppd increase in vaccine hesitancy. There were significant interactions between refugee status and some variables (geography, food security, trust in the Kenyan government’s response to COVID-19, knowing somebody with COVID-19, internet use, and TV ownership). These relationships between refugee status and certain variables suggest that programming between refugees and non-refugees be differentiated and specific to the contextual needs of each group

Scratch and match : pigeons learn matching and oddity with gravel stimuli

Two groups of 4 pigeons learned either matching-to-sample or oddity-from-sample by digging in white and black gravel for buried grain. Learning occurred as early as Trial 11, and acquisition was accelerated by as much as 100-fold compared with learning in traditional key-peck environments. Control experiments showed that performance was not controlled by cues other than the gravel stimuli and was not due to distributed practice effects of 8 trials per day and longer intertrial intervals

Learning processes in matching and oddity : the oddity preference effect and sample reinforcement

Eight pigeons learned either matching (to sample) or oddity (from sample) with or without reward for sample responding. The training stimuli were coarse-white, fine-black, or smooth-mauve gravels in pots with buried grain as the reinforcer. Oddity without sample reward was learned most rapidly, followed by matching with sample reward, oddity with sample reward, and matching without sample reward. Transfer was related to acquisition rate: The oddity group without sample reward showed full (equal to baseline) color and texture transfer; the matching group with sample reward showed partial texture transfer; other groups showed no transfer. Sample reward was shown to determine rate of acquisition of matching and oddity and the oddity preference effect. The results are discussed in terms of item-specific associations operating early in learning prior to any relational learning between sample and comparison stimuli

Transitive responding in pigeons : influences of stimulus frequency and reinforcement history

Fersen et al. (1991) (J. Exp. Psychol.: Anim. Behav. Process., 17: 334–341) trained pigeons to discriminate four overlapping pairs of stimuli A + B −, B + C −, C + D − and D + E − (+ rewarded, − penalized). When subsequently tested with a pair BD the pigeons showed a strong preference for stimulus B. A special value transfer theory was offered as an explanation for this transitive responding. A simpler reinforcement ratio account based on certain inequalities factually affecting the accuracy performance on training pairs is proposed. To explore its implications an experiment employing a novel grit-grain conditioning method was carried out. The presentation frequencies of the training pairs were biased so that the choice accuracies obtained at the end of training were approximately equal for all pairs. Testing with pair BD still yielded high preference for B, documenting the robustness of the transitive responding phenomenon. When suitably adjusted to the training design the reinforcement ratio account was still viable. The transitive responding with the BD and other test pairs could also be simulated with a simple reinforcement based conditioning model. Some of the subjects were then retrained with modified presentation frequencies so that the subjects ended up with an even overall exposure to all training pairs. Test pairs continued to yield strong transitive responding. It is concluded that this behavioral effect is a robust phenomenon which is largely unaffected by training design modifications

Estrategias de mercado para incrementar el desarrollo comercial de la clínica odontológica Bonilla Pedraza Bucaramanga en el periodo de marzo a julio de 2017

Con el trabajo se logró aplicar la Matriz DOFA en la Clínica BONILLA PEDRAZA permitió reconocer que una de sus mayores Fortalezas es la Política de Calidad bien definida en cada uno de los procesos y procedimientos, así como la buena atención basada en principios de solidaridad, respeto y ética. El análisis de la Oferta determinó que la mayor parte de las personas que necesitan los servicios odontológicos tanto preventivos como curativos, son de la zona urbana y de sexo femenino. Es prioridad para la Clínica BONILLA PEDRAZA diseñar un Plan de Mercadeo y Publicidad que brinde herramientas publicitarias y de mercado para aumentar la cantidad de pacientes atendidos y por tanto obtener mayor productividad.PregradoAdministrador(a) de Los Servicios de la Salu

Concept learning by pigeons : matching-to-sample with trial-unique video picture stimuli

Pigeons were trained to match-to-sample with several new methodologies: a large number of stimuli, computer-drawn color picture stimuli, responses monitored by a computer touch screen, stimuli presented horizontally from the floor, and grain reinforcement delivered onto the picture stimuli. Following acquisition, matching-to-sample concept learning was assessed by transfer to novel stimuli on the first exposure to pairs of novel stimuli. One group (trial-unique), trained with 152 different pictures presented once daily, showed excellent transfer (80% correct). Transfer and baseline performances were equivalent, indicating that the matching-to-sample concept had been learned. A second group (2-stimulus), trained with only two different pictures, showed no evidence of transfer. These results are discussed in terms of the effect of numbers of exemplars on previous failures to find concept learning in pigeons, and the implications of the positive finding from this experiment on abstract concept learning and evolutionary cognitive development

Optimized syntheses of optically pure p-alkene ligands: crystal structures of a pair of p-stereogenic diastereomers

The ‘privileged’ P-alkene ligand (S)-2 is synthesized on a > 40 gram scale in 96% yield starting from dibenz[b,f]azepine-PCl2 (1; accessible on > 80 g scale) and (S)-BINOL. Similarly, the P-alkenes (R)-3 and the ‘chiral-at-P’ (SP,SC)-4 are obtained from (R)-Taddol [(R,R)-α,α,α', α'-tetraphenyl-2,2-dimethyl-1,3-dioxolane-4,5-dimethanol] and (S)-α,α-diphenylprolinol, respectively, in multigram quantities and high purity. The crystal structures of (SP,SC)-4, its diastereomer (RP,SC)-4, and of the(R)-SPINOL-derived ligand (R)-5 are reported. A slightly revised synthesis of SPINOL is also disclosed